1. Technical Field
This invention relates generally to irrigation equipment, and more particularly to a new and improved emitter for drip irrigation applications.
2. Background Information
Rather than spraying water over a field of crops, drip irrigation equipment supplies the water drip-by-drip near the roots where it does the most good. Some drip irrigation accomplishes this with water emitting devices or emitters that are mounted at spaced apart locations along a supply tube. The emitters control the flow of water so that it discharges very slowly.
Existing emitters for this purpose may include an emitter body that may be cylindrically shaped and about two centimeters in diameter, for example. A stem extends axially from the emitter body for insertion through a hole in the supply tube and a barb on the stem engages the tube. Using a supply of these emitters, a user inserts them at selected locations along the tube to achieve the desired irrigation, at twenty centimeter intervals, for example.
The stem defines an emitter inlet through which water flows from the supply tube into the emitter. There, the water flows along a turbulent flow passage to an emitter outlet. As this happens, the turbulent flow passage dissipates flow energy (reduces the water pressure) so that the water drips out slowly at a desired rate, and it is the structure defining the turbulent flow passage in existing emitters that could be improved.
The turbulent flow passage in some existing emitters, for example, is cooperatively defined by three injection molded members. A first member (that may be disc-shaped, for example) includes a channel in opposing faces of the disc that extends along a tortuous path. The second and third members screw or snap together over the first member to cover the channel and thereby form a water tight turbulent flow passage. However, three injection molded components are required.
Another existing emitter reduces the number of components from two to three by using a barrel-shaped member having a channel in its outer peripheral surface. The channel is covered with another molded member that fits tightly over the barrel-shaped member. This arrangement forms the desired turbulent flow passage with just two components, but they are tightly fitting injection molded components.
Thus, existing emitters may involve components that are somewhat complicated, costly, and inconvenient to fabricate. In addition, the fit may deteriorate as water pressure increases. Consequently, it is desirable to have a new and improved emitter that alleviates these concerns.